Trolley retriever



Jan. 9,1923. 1,441,500. e. E. HARPHAM, v

TROLLEY RETRIEVER.

ORIGINAL FILED MAY 16, I918.

Patented Jan. 9, 1923.

FATE.

GEORGE E. HARPHAM, or LOS ANGELES, CALIFORNIA.

TRO LEY nn'rnrnvna.

Original application'filed. May 16, 1918, Serial No. 234,940, Divided and this application filed June 13,

1921. Serial No. 477,142..

T0 all whom it may concern:

Be it known that LGEORGE E. HARPHAM, a citizen of the United States, residing at the city of Los Angeles, county of Los Angeles, State of California, have inventednew and useful Improvements in Trolley Retrievers, of which the following is a specification.

My invention relates to trolley retrievers for electrically operated cars to which the power is conveyed bymeans of overhead feed wires; and the object thereof is to provide improved mechanism for lowering the trolley pole when its conducting wheel leaves the feed wire. A further objectis to provide a mechanism that furnishes a cushion to prevent the trolley wheel striking thereof of thecar when it is lowered.

The drawing is a side elevation partly in section of that portion of a trolley which embraces my invention, the usual spring mechanism for raising the wheel to the feed wire being omitted. for clearness of illustrat-ion. 7

Referring to the drawings, 5 is the base plate which is secured upon the car roof (not shown). A hollow bolt 6 secures the base member 7 of the trolley pole which 7 member is revolubly mounted on plate 5.

- wheel (not shown).

- connected by An L-shaped bracket 8 forming the pole base, carries the trolley pole 9 on the end of which is carried thev usual conductor The lower member of bracket 8 is bifurcated and is pivotally secured to' base 7 by bolt 10. Base 7 has upwardly extending arms 11 in which is rockably mounted the air cylinder 12. A piston 13' is mounted in cylinder 12 and has a stem 1 1 that is pivotally connected to the upper arm of bracket 8 by bolt 15. On the rear head of cylinder 12 is a valve chamber casing 16 which forms valve chamber 17. A pipe 18 connects chamber 17 toa source of compressed air supply (not shown) in the usual manner. Valve chamber 17 is lport 20 with the interior of cylinder 12. ort 20 is normally closed by valve 21 which has a hollow stem 22 which extends through port 20. Valve 21 under normal running conditions prevents the compressed air from entering the rear end of cylinder 12. On the inner end of stem 22 is screwed or otherwise secured a piston 23 which has a loose working fit in cylinder 12 and is normally held a short distance in front of the rear head 12 of cylinder 12. lVithin chamber 17 valve 21 has a reduced portion. A port 25 connects pipe 18 with chamber 17; A port 26 leads out of chamber 17 and is connected bypipe 27 with the front end of cylinder 12. Ports 25 and 26 are'in staggered relation to each other. Ports28 are provided in disk 23 and ports'29 in head 12 whichports are preferably offset, with ports29 larger than ports 28. These ports permit of a-normal' flowv of air into and out of cylinder 12 under "running conditions' The rear end of casing 16 is closed by a cap 30 which has a port 31 therein. Port 31 is normally closed by a valve 32 having a' stem 33 which enters a guide channel 341 in the end of Valve 21. Valve 32 is held normally closed by spring 35 coiled around the stem and having one end bearing against cap 30 and the other endagainst a pin 36 which pin eXtends through stem 33.

In operation the conductorwheel is held in engagement with the feed wire by spring and air pressure but in this construction the air passes through pipe 18, chamber 17 and pipe 27 and then into the front end of cylinder 12. When the conductor wheel leaves the feed wire while the car is running, pis ton 13 is caused to rapidly approach the rear head, thereby compressing the air between piston 13 and piston 23 which causes piston 23 to seat itself on the rear end of the cylinder and to carry valve 21 off its seat and to cause the front end of the same to pass back of the entrance of pipe 18 into chamber 17 and thereby cut off the flow of air to the front end of chamber 12. then enters cylinder 12 through ports 37 and the channel in stem 22 and forces piston 13 toward the front end of the cylinder, thereby depressing the conductor wheel. The initial movement of valve 21 will un- Air seat valve 32 and thereby relieve any air I pressure in chamber 17 back of valve 21. After the an pressure 1s relieved in cylinder 12 spring 39 returns valve 21 and connected parts to their normal position. I

By this construction it will be seen that as soon as the conductor wheel leaves the feed, wire the full air. pressure. is applied 3 as the piston in the cylinder reaches the piston on the stem of such valve, the valve will be unseated and air pressure will be applied to the full rear face of piston 13 and the wheel will then be quickly brought down below the over head feed wire. It will be observed that all the air in the for ward end of cylinder 12 is trapped when valve 21 is unseated and acts as a cushion to prevent the conductor wheel from striking the roof of the car. Piston 23 has spacing knobs 40 that keep pistons 13 and 23 separated to permit air to be between them at all times. Instead of a port in piston 23 there could be suiiicient clearance for the flow or the air around the piston for usual running conditions. My re trieving device could be used with those trolleys where the conductor wheel is held in contact with the feed wire by spring pressure. In such case it is onlynecessary to provide air pressure for the valve chamber on the rear end of cylinder 12. This application is a division of my application No. 234,940 filed May 16th 1918.

Having described my invention, I claim:

1. In a trolley retriever the combination of an air cylinder having front and rear heads, said rear headhaving ports therein a valve chamber mounted upon the rear head 01' said cylinder in communication with the interior of said cylinder through a port in said rear head; a pipe opening into said valve chamber and adapted to supply com pressed air thereinto; a pipe leading from said chamber and opening into the front end ofsaid cylinder; a valve in said chamher; said valve having a hollow stem provided with ports and normally closing communication between said chamber and cylinder; a piston having ports therein mounted 'upon said stem within said cylinder; another piston within said cylinder; and a trolley pole operatively connected to said last piston.

2. In a trolley retriever, a trolley pole;

an air, cylinder; a piston in said cylinder operatively [connected to said pole and adapted to move the free end of the pole either upwardly or downwardly; a valve chamber at the rear end of said cylinder in communication with the interior of the cylinder through an opening in the rear head; apipec connected to said chamber adapted to supply compressed air thereinto; a pipe connecting saidchamber with the front" end of said cylinder; a valve in said chamber adapted to change the air pressure from the front to the rear end of the 

